Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

Pull networking fixes from David Miller:

 1) Missing cancel of work items in mac80211 MLME, from Ben Greear.

 2) Fix DMA mapping handling in iwlwifi by using coherent DMA for
    command headers, from Johannes Berg.

 3) Decrease the amount of pressure on the page allocator by using order
    1 pages less in iwlwifi, from Emmanuel Grumbach.

 4) Fix mesh PS broadcast OOPS in mac80211, from Marco Porsch.

 5) Don't forget to recalculate idle state in mac80211 monitor
    interface, from Felix Fietkau.

 6) Fix varargs in netfilter conntrack handler, from Joe Perches.

 7) Need to reset entire chip when command queue fills up in iwlwifi,
    from Emmanuel Grumbach.

 8) The TX antenna value must be valid when calibrations are performed
    in iwlwifi, fix from Dor Shaish.

 9) Don't generate netfilter audit log entries when audit is disabled,
    from Gao Feng.

10) Deal with DMA unit hang on e1000e during power state transitions,
    from Bruce Allan.

11) Remove BUILD_BUG_ON check from igb driver, from Alexander Duyck.

12) Fix lockdep warning on i2c handling of igb driver, from Carolyn
    Wyborny.

13) Fix several TTY handling issues in IRDA ircomm tty driver, from
    Peter Hurley.

14) Several QFQ packet scheduler fixes from Paolo Valente.

15) When VXLAN encapsulates on transmit, we have to reset the netfilter
    state.  From Zang MingJie.

16) Fix jiffie check in net_rx_action() so that we really cap the
    processing at 2HZ.  From Eric Dumazet.

17) Fix erroneous trigger of IP option space exhaustion, when routers
    are pre-specified and we are looking to see if we can insert a
    timestamp, we will have the space.  From David Ward.

18) Fix various issues in benet driver wrt waiting for firmware to
    finish POST after resets or errors.  From Gavin Shan and Sathya
    Perla.

19) Fix TX locking in SFC driver, from Ben Hutchings.

20) Like the VXLAN fix above, when we encap in a TUN device we have to
    reset the netfilter state.  This should fix several strange crashes
    reported by Dave Jones and others.  From Eric Dumazet.

21) Don't forget to clean up MAC address resources when shutting down a
    port in mlx4 driver, from Yan Burman.

22) Fix divide by zero in vmxnet3 driver, from Bhavesh Davda.

23) Fix device statistic regression in tg3 when the driver is using
    phylib, from Nithin Sujir.

24) Fix info leak in several netlink handlers, from Mathias Krause.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (79 commits)
  6lowpan: Fix endianness issue in is_addr_link_local().
  rrunner.c: fix possible memory leak in rr_init_one()
  dcbnl: fix various netlink info leaks
  rtnl: fix info leak on RTM_GETLINK request for VF devices
  bridge: fix mdb info leaks
  tg3: Update link_up flag for phylib devices
  ipv6: stop multicast forwarding to process interface scoped addresses
  bridging: fix rx_handlers return code
  netlabel: fix build problems when CONFIG_IPV6=n
  drivers/isdn: checkng length to be sure not memory overflow
  net/rds: zero last byte for strncpy
  bnx2x: Fix SFP+ misconfiguration in iSCSI boot scenario
  bnx2x: Fix intermittent long KR2 link up time
  macvlan: Set IFF_UNICAST_FLT flag to prevent unnecessary promisc mode.
  team: unsyc the devices addresses when port is removed
  bridge: add missing vid to br_mdb_get()
  Fix: sparse warning in inet_csk_prepare_forced_close
  afkey: fix a typo
  MAINTAINERS: Update qlcnic maintainers list
  netlabel: correctly list all the static label mappings
  ...

1 files changed, 124 insertions, 142 deletions

diff --git a/drivers/net/wireless/iwlwifi/pcie/tx.c b/drivers/net/wireless/iwlwifi/pcie/tx.c
index 8b625a7f5685..8595c16f74de 100644
--- a/drivers/net/wireless/iwlwifi/pcie/tx.c
+++ b/drivers/net/wireless/iwlwifi/pcie/tx.c
@@ -191,12 +191,9 @@ static void iwl_pcie_txq_stuck_timer(unsigned long data)
         }
 
         for (i = q->read_ptr; i != q->write_ptr;
-             i = iwl_queue_inc_wrap(i, q->n_bd)) {
-                struct iwl_tx_cmd *tx_cmd =
-                        (struct iwl_tx_cmd *)txq->entries[i].cmd->payload;
+             i = iwl_queue_inc_wrap(i, q->n_bd))
                 IWL_ERR(trans, "scratch %d = 0x%08x\n", i,
-                        get_unaligned_le32(&tx_cmd->scratch));
-        }
+                        le32_to_cpu(txq->scratchbufs[i].scratch));
 
         iwl_op_mode_nic_error(trans->op_mode);
 }
@@ -367,8 +364,8 @@ static inline u8 iwl_pcie_tfd_get_num_tbs(struct iwl_tfd *tfd)
 }
 
 static void iwl_pcie_tfd_unmap(struct iwl_trans *trans,
-                               struct iwl_cmd_meta *meta, struct iwl_tfd *tfd,
-                               enum dma_data_direction dma_dir)
+                               struct iwl_cmd_meta *meta,
+                               struct iwl_tfd *tfd)
 {
         int i;
         int num_tbs;
@@ -382,17 +379,12 @@ static void iwl_pcie_tfd_unmap(struct iwl_trans *trans,
                 return;
         }
 
-        /* Unmap tx_cmd */
-        if (num_tbs)
-                dma_unmap_single(trans->dev,
-                                dma_unmap_addr(meta, mapping),
-                                dma_unmap_len(meta, len),
-                                DMA_BIDIRECTIONAL);
+        /* first TB is never freed - it's the scratchbuf data */
 
-        /* Unmap chunks, if any. */
         for (i = 1; i < num_tbs; i++)
                 dma_unmap_single(trans->dev, iwl_pcie_tfd_tb_get_addr(tfd, i),
-                                 iwl_pcie_tfd_tb_get_len(tfd, i), dma_dir);
+                                 iwl_pcie_tfd_tb_get_len(tfd, i),
+                                 DMA_TO_DEVICE);
 
         tfd->num_tbs = 0;
 }
@@ -406,8 +398,7 @@ static void iwl_pcie_tfd_unmap(struct iwl_trans *trans,
  * Does NOT advance any TFD circular buffer read/write indexes
  * Does NOT free the TFD itself (which is within circular buffer)
  */
-static void iwl_pcie_txq_free_tfd(struct iwl_trans *trans, struct iwl_txq *txq,
-                                  enum dma_data_direction dma_dir)
+static void iwl_pcie_txq_free_tfd(struct iwl_trans *trans, struct iwl_txq *txq)
 {
         struct iwl_tfd *tfd_tmp = txq->tfds;
 
@@ -418,8 +409,7 @@ static void iwl_pcie_txq_free_tfd(struct iwl_trans *trans, struct iwl_txq *txq,
         lockdep_assert_held(&txq->lock);
 
         /* We have only q->n_window txq->entries, but we use q->n_bd tfds */
-        iwl_pcie_tfd_unmap(trans, &txq->entries[idx].meta, &tfd_tmp[rd_ptr],
-                           dma_dir);
+        iwl_pcie_tfd_unmap(trans, &txq->entries[idx].meta, &tfd_tmp[rd_ptr]);
 
         /* free SKB */
         if (txq->entries) {
@@ -479,6 +469,7 @@ static int iwl_pcie_txq_alloc(struct iwl_trans *trans,
 {
         struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
         size_t tfd_sz = sizeof(struct iwl_tfd) * TFD_QUEUE_SIZE_MAX;
+        size_t scratchbuf_sz;
         int i;
 
         if (WARN_ON(txq->entries || txq->tfds))
@@ -514,9 +505,25 @@ static int iwl_pcie_txq_alloc(struct iwl_trans *trans,
                 IWL_ERR(trans, "dma_alloc_coherent(%zd) failed\n", tfd_sz);
                 goto error;
         }
+
+        BUILD_BUG_ON(IWL_HCMD_SCRATCHBUF_SIZE != sizeof(*txq->scratchbufs));
+        BUILD_BUG_ON(offsetof(struct iwl_pcie_txq_scratch_buf, scratch) !=
+                        sizeof(struct iwl_cmd_header) +
+                        offsetof(struct iwl_tx_cmd, scratch));
+
+        scratchbuf_sz = sizeof(*txq->scratchbufs) * slots_num;
+
+        txq->scratchbufs = dma_alloc_coherent(trans->dev, scratchbuf_sz,
+                                              &txq->scratchbufs_dma,
+                                              GFP_KERNEL);
+        if (!txq->scratchbufs)
+                goto err_free_tfds;
+
         txq->q.id = txq_id;
 
         return 0;
+err_free_tfds:
+        dma_free_coherent(trans->dev, tfd_sz, txq->tfds, txq->q.dma_addr);
 error:
         if (txq->entries && txq_id == trans_pcie->cmd_queue)
                 for (i = 0; i < slots_num; i++)
@@ -565,22 +572,13 @@ static void iwl_pcie_txq_unmap(struct iwl_trans *trans, int txq_id)
         struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
         struct iwl_txq *txq = &trans_pcie->txq[txq_id];
         struct iwl_queue *q = &txq->q;
-        enum dma_data_direction dma_dir;
 
         if (!q->n_bd)
                 return;
 
-        /* In the command queue, all the TBs are mapped as BIDI
-         * so unmap them as such.
-         */
-        if (txq_id == trans_pcie->cmd_queue)
-                dma_dir = DMA_BIDIRECTIONAL;
-        else
-                dma_dir = DMA_TO_DEVICE;
-
         spin_lock_bh(&txq->lock);
         while (q->write_ptr != q->read_ptr) {
-                iwl_pcie_txq_free_tfd(trans, txq, dma_dir);
+                iwl_pcie_txq_free_tfd(trans, txq);
                 q->read_ptr = iwl_queue_inc_wrap(q->read_ptr, q->n_bd);
         }
         spin_unlock_bh(&txq->lock);
@@ -610,7 +608,6 @@ static void iwl_pcie_txq_free(struct iwl_trans *trans, int txq_id)
         if (txq_id == trans_pcie->cmd_queue)
                 for (i = 0; i < txq->q.n_window; i++) {
                         kfree(txq->entries[i].cmd);
-                        kfree(txq->entries[i].copy_cmd);
                         kfree(txq->entries[i].free_buf);
                 }
 
@@ -619,6 +616,10 @@ static void iwl_pcie_txq_free(struct iwl_trans *trans, int txq_id)
                 dma_free_coherent(dev, sizeof(struct iwl_tfd) *
                                   txq->q.n_bd, txq->tfds, txq->q.dma_addr);
                 txq->q.dma_addr = 0;
+
+                dma_free_coherent(dev,
+                                  sizeof(*txq->scratchbufs) * txq->q.n_window,
+                                  txq->scratchbufs, txq->scratchbufs_dma);
         }
 
         kfree(txq->entries);
@@ -962,7 +963,7 @@ void iwl_trans_pcie_reclaim(struct iwl_trans *trans, int txq_id, int ssn,
 
                 iwl_pcie_txq_inval_byte_cnt_tbl(trans, txq);
 
-                iwl_pcie_txq_free_tfd(trans, txq, DMA_TO_DEVICE);
+                iwl_pcie_txq_free_tfd(trans, txq);
         }
 
         iwl_pcie_txq_progress(trans_pcie, txq);
@@ -1152,29 +1153,29 @@ static int iwl_pcie_enqueue_hcmd(struct iwl_trans *trans,
         void *dup_buf = NULL;
         dma_addr_t phys_addr;
         int idx;
-        u16 copy_size, cmd_size, dma_size;
+        u16 copy_size, cmd_size, scratch_size;
         bool had_nocopy = false;
         int i;
         u32 cmd_pos;
-        const u8 *cmddata[IWL_MAX_CMD_TFDS];
-        u16 cmdlen[IWL_MAX_CMD_TFDS];
+        const u8 *cmddata[IWL_MAX_CMD_TBS_PER_TFD];
+        u16 cmdlen[IWL_MAX_CMD_TBS_PER_TFD];
 
         copy_size = sizeof(out_cmd->hdr);
         cmd_size = sizeof(out_cmd->hdr);
 
         /* need one for the header if the first is NOCOPY */
-        BUILD_BUG_ON(IWL_MAX_CMD_TFDS > IWL_NUM_OF_TBS - 1);
+        BUILD_BUG_ON(IWL_MAX_CMD_TBS_PER_TFD > IWL_NUM_OF_TBS - 1);
 
-        for (i = 0; i < IWL_MAX_CMD_TFDS; i++) {
+        for (i = 0; i < IWL_MAX_CMD_TBS_PER_TFD; i++) {
                 cmddata[i] = cmd->data[i];
                 cmdlen[i] = cmd->len[i];
 
                 if (!cmd->len[i])
                         continue;
 
-                /* need at least IWL_HCMD_MIN_COPY_SIZE copied */
-                if (copy_size < IWL_HCMD_MIN_COPY_SIZE) {
-                        int copy = IWL_HCMD_MIN_COPY_SIZE - copy_size;
+                /* need at least IWL_HCMD_SCRATCHBUF_SIZE copied */
+                if (copy_size < IWL_HCMD_SCRATCHBUF_SIZE) {
+                        int copy = IWL_HCMD_SCRATCHBUF_SIZE - copy_size;
 
                         if (copy > cmdlen[i])
                                 copy = cmdlen[i];
@@ -1260,15 +1261,15 @@ static int iwl_pcie_enqueue_hcmd(struct iwl_trans *trans,
         /* and copy the data that needs to be copied */
         cmd_pos = offsetof(struct iwl_device_cmd, payload);
         copy_size = sizeof(out_cmd->hdr);
-        for (i = 0; i < IWL_MAX_CMD_TFDS; i++) {
+        for (i = 0; i < IWL_MAX_CMD_TBS_PER_TFD; i++) {
                 int copy = 0;
 
                 if (!cmd->len)
                         continue;
 
-                /* need at least IWL_HCMD_MIN_COPY_SIZE copied */
-                if (copy_size < IWL_HCMD_MIN_COPY_SIZE) {
-                        copy = IWL_HCMD_MIN_COPY_SIZE - copy_size;
+                /* need at least IWL_HCMD_SCRATCHBUF_SIZE copied */
+                if (copy_size < IWL_HCMD_SCRATCHBUF_SIZE) {
+                        copy = IWL_HCMD_SCRATCHBUF_SIZE - copy_size;
 
                         if (copy > cmd->len[i])
                                 copy = cmd->len[i];
@@ -1286,50 +1287,38 @@ static int iwl_pcie_enqueue_hcmd(struct iwl_trans *trans,
                 }
         }
 
-        WARN_ON_ONCE(txq->entries[idx].copy_cmd);
-
-        /*
-         * since out_cmd will be the source address of the FH, it will write
-         * the retry count there. So when the user needs to receivce the HCMD
-         * that corresponds to the response in the response handler, it needs
-         * to set CMD_WANT_HCMD.
-         */
-        if (cmd->flags & CMD_WANT_HCMD) {
-                txq->entries[idx].copy_cmd =
-                        kmemdup(out_cmd, cmd_pos, GFP_ATOMIC);
-                if (unlikely(!txq->entries[idx].copy_cmd)) {
-                        idx = -ENOMEM;
-                        goto out;
-                }
-        }
-
         IWL_DEBUG_HC(trans,
                      "Sending command %s (#%x), seq: 0x%04X, %d bytes at %d[%d]:%d\n",
                      get_cmd_string(trans_pcie, out_cmd->hdr.cmd),
                      out_cmd->hdr.cmd, le16_to_cpu(out_cmd->hdr.sequence),
                      cmd_size, q->write_ptr, idx, trans_pcie->cmd_queue);
 
-        /*
-         * If the entire command is smaller than IWL_HCMD_MIN_COPY_SIZE, we must
-         * still map at least that many bytes for the hardware to write back to.
-         * We have enough space, so that's not a problem.
-         */
-        dma_size = max_t(u16, copy_size, IWL_HCMD_MIN_COPY_SIZE);
+        /* start the TFD with the scratchbuf */
+        scratch_size = min_t(int, copy_size, IWL_HCMD_SCRATCHBUF_SIZE);
+        memcpy(&txq->scratchbufs[q->write_ptr], &out_cmd->hdr, scratch_size);
+        iwl_pcie_txq_build_tfd(trans, txq,
+                               iwl_pcie_get_scratchbuf_dma(txq, q->write_ptr),
+                               scratch_size, 1);
+
+        /* map first command fragment, if any remains */
+        if (copy_size > scratch_size) {
+                phys_addr = dma_map_single(trans->dev,
+                                           ((u8 *)&out_cmd->hdr) + scratch_size,
+                                           copy_size - scratch_size,
+                                           DMA_TO_DEVICE);
+                if (dma_mapping_error(trans->dev, phys_addr)) {
+                        iwl_pcie_tfd_unmap(trans, out_meta,
+                                           &txq->tfds[q->write_ptr]);
+                        idx = -ENOMEM;
+                        goto out;
+                }
 
-        phys_addr = dma_map_single(trans->dev, &out_cmd->hdr, dma_size,
-                                   DMA_BIDIRECTIONAL);
-        if (unlikely(dma_mapping_error(trans->dev, phys_addr))) {
-                idx = -ENOMEM;
-                goto out;
+                iwl_pcie_txq_build_tfd(trans, txq, phys_addr,
+                                       copy_size - scratch_size, 0);
         }
 
-        dma_unmap_addr_set(out_meta, mapping, phys_addr);
-        dma_unmap_len_set(out_meta, len, dma_size);
-
-        iwl_pcie_txq_build_tfd(trans, txq, phys_addr, copy_size, 1);
-
         /* map the remaining (adjusted) nocopy/dup fragments */
-        for (i = 0; i < IWL_MAX_CMD_TFDS; i++) {
+        for (i = 0; i < IWL_MAX_CMD_TBS_PER_TFD; i++) {
                 const void *data = cmddata[i];
 
                 if (!cmdlen[i])
@@ -1340,11 +1329,10 @@ static int iwl_pcie_enqueue_hcmd(struct iwl_trans *trans,
                 if (cmd->dataflags[i] & IWL_HCMD_DFL_DUP)
                         data = dup_buf;
                 phys_addr = dma_map_single(trans->dev, (void *)data,
-                                           cmdlen[i], DMA_BIDIRECTIONAL);
+                                           cmdlen[i], DMA_TO_DEVICE);
                 if (dma_mapping_error(trans->dev, phys_addr)) {
                         iwl_pcie_tfd_unmap(trans, out_meta,
-                                           &txq->tfds[q->write_ptr],
-                                           DMA_BIDIRECTIONAL);
+                                           &txq->tfds[q->write_ptr]);
                         idx = -ENOMEM;
                         goto out;
                 }
@@ -1418,7 +1406,7 @@ void iwl_pcie_hcmd_complete(struct iwl_trans *trans,
         cmd = txq->entries[cmd_index].cmd;
         meta = &txq->entries[cmd_index].meta;
 
-        iwl_pcie_tfd_unmap(trans, meta, &txq->tfds[index], DMA_BIDIRECTIONAL);
+        iwl_pcie_tfd_unmap(trans, meta, &txq->tfds[index]);
 
         /* Input error checking is done when commands are added to queue. */
         if (meta->flags & CMD_WANT_SKB) {
@@ -1597,10 +1585,9 @@ int iwl_trans_pcie_tx(struct iwl_trans *trans, struct sk_buff *skb,
         struct iwl_cmd_meta *out_meta;
         struct iwl_txq *txq;
         struct iwl_queue *q;
-        dma_addr_t phys_addr = 0;
-        dma_addr_t txcmd_phys;
-        dma_addr_t scratch_phys;
-        u16 len, firstlen, secondlen;
+        dma_addr_t tb0_phys, tb1_phys, scratch_phys;
+        void *tb1_addr;
+        u16 len, tb1_len, tb2_len;
         u8 wait_write_ptr = 0;
         __le16 fc = hdr->frame_control;
         u8 hdr_len = ieee80211_hdrlen(fc);
@@ -1638,85 +1625,80 @@ int iwl_trans_pcie_tx(struct iwl_trans *trans, struct sk_buff *skb,
                 cpu_to_le16((u16)(QUEUE_TO_SEQ(txq_id) |
                             INDEX_TO_SEQ(q->write_ptr)));
 
+        tb0_phys = iwl_pcie_get_scratchbuf_dma(txq, q->write_ptr);
+        scratch_phys = tb0_phys + sizeof(struct iwl_cmd_header) +
+                       offsetof(struct iwl_tx_cmd, scratch);
+
+        tx_cmd->dram_lsb_ptr = cpu_to_le32(scratch_phys);
+        tx_cmd->dram_msb_ptr = iwl_get_dma_hi_addr(scratch_phys);
+
         /* Set up first empty entry in queue's array of Tx/cmd buffers */
         out_meta = &txq->entries[q->write_ptr].meta;
 
         /*
-         * Use the first empty entry in this queue's command buffer array
-         * to contain the Tx command and MAC header concatenated together
-         * (payload data will be in another buffer).
-         * Size of this varies, due to varying MAC header length.
-         * If end is not dword aligned, we'll have 2 extra bytes at the end
-         * of the MAC header (device reads on dword boundaries).
-         * We'll tell device about this padding later.
+         * The second TB (tb1) points to the remainder of the TX command
+         * and the 802.11 header - dword aligned size
+         * (This calculation modifies the TX command, so do it before the
+         * setup of the first TB)
          */
-        len = sizeof(struct iwl_tx_cmd) +
-                sizeof(struct iwl_cmd_header) + hdr_len;
-        firstlen = (len + 3) & ~3;
+        len = sizeof(struct iwl_tx_cmd) + sizeof(struct iwl_cmd_header) +
+              hdr_len - IWL_HCMD_SCRATCHBUF_SIZE;
+        tb1_len = (len + 3) & ~3;
 
         /* Tell NIC about any 2-byte padding after MAC header */
-        if (firstlen != len)
+        if (tb1_len != len)
                 tx_cmd->tx_flags |= TX_CMD_FLG_MH_PAD_MSK;
 
-        /* Physical address of this Tx command's header (not MAC header!),
-         * within command buffer array. */
-        txcmd_phys = dma_map_single(trans->dev,
-                                    &dev_cmd->hdr, firstlen,
-                                    DMA_BIDIRECTIONAL);
-        if (unlikely(dma_mapping_error(trans->dev, txcmd_phys)))
-                goto out_err;
-        dma_unmap_addr_set(out_meta, mapping, txcmd_phys);
-        dma_unmap_len_set(out_meta, len, firstlen);
+        /* The first TB points to the scratchbuf data - min_copy bytes */
+        memcpy(&txq->scratchbufs[q->write_ptr], &dev_cmd->hdr,
+               IWL_HCMD_SCRATCHBUF_SIZE);
+        iwl_pcie_txq_build_tfd(trans, txq, tb0_phys,
+                               IWL_HCMD_SCRATCHBUF_SIZE, 1);
 
-        if (!ieee80211_has_morefrags(fc)) {
-                txq->need_update = 1;
-        } else {
-                wait_write_ptr = 1;
-                txq->need_update = 0;
-        }
+        /* there must be data left over for TB1 or this code must be changed */
+        BUILD_BUG_ON(sizeof(struct iwl_tx_cmd) < IWL_HCMD_SCRATCHBUF_SIZE);
 
-        /* Set up TFD's 2nd entry to point directly to remainder of skb,
-         * if any (802.11 null frames have no payload). */
-        secondlen = skb->len - hdr_len;
-        if (secondlen > 0) {
-                phys_addr = dma_map_single(trans->dev, skb->data + hdr_len,
-                                           secondlen, DMA_TO_DEVICE);
-                if (unlikely(dma_mapping_error(trans->dev, phys_addr))) {
-                        dma_unmap_single(trans->dev,
-                                         dma_unmap_addr(out_meta, mapping),
-                                         dma_unmap_len(out_meta, len),
-                                         DMA_BIDIRECTIONAL);
+        /* map the data for TB1 */
+        tb1_addr = ((u8 *)&dev_cmd->hdr) + IWL_HCMD_SCRATCHBUF_SIZE;
+        tb1_phys = dma_map_single(trans->dev, tb1_addr, tb1_len, DMA_TO_DEVICE);
+        if (unlikely(dma_mapping_error(trans->dev, tb1_phys)))
+                goto out_err;
+        iwl_pcie_txq_build_tfd(trans, txq, tb1_phys, tb1_len, 0);
+
+        /*
+         * Set up TFD's third entry to point directly to remainder
+         * of skb, if any (802.11 null frames have no payload).
+         */
+        tb2_len = skb->len - hdr_len;
+        if (tb2_len > 0) {
+                dma_addr_t tb2_phys = dma_map_single(trans->dev,
+                                                     skb->data + hdr_len,
+                                                     tb2_len, DMA_TO_DEVICE);
+                if (unlikely(dma_mapping_error(trans->dev, tb2_phys))) {
+                        iwl_pcie_tfd_unmap(trans, out_meta,
+                                           &txq->tfds[q->write_ptr]);
                         goto out_err;
                 }
+                iwl_pcie_txq_build_tfd(trans, txq, tb2_phys, tb2_len, 0);
         }
 
-        /* Attach buffers to TFD */
-        iwl_pcie_txq_build_tfd(trans, txq, txcmd_phys, firstlen, 1);
-        if (secondlen > 0)
-                iwl_pcie_txq_build_tfd(trans, txq, phys_addr, secondlen, 0);
-
-        scratch_phys = txcmd_phys + sizeof(struct iwl_cmd_header) +
-                                offsetof(struct iwl_tx_cmd, scratch);
-
-        /* take back ownership of DMA buffer to enable update */
-        dma_sync_single_for_cpu(trans->dev, txcmd_phys, firstlen,
-                                DMA_BIDIRECTIONAL);
-        tx_cmd->dram_lsb_ptr = cpu_to_le32(scratch_phys);
-        tx_cmd->dram_msb_ptr = iwl_get_dma_hi_addr(scratch_phys);
-
         /* Set up entry for this TFD in Tx byte-count array */
         iwl_pcie_txq_update_byte_cnt_tbl(trans, txq, le16_to_cpu(tx_cmd->len));
 
-        dma_sync_single_for_device(trans->dev, txcmd_phys, firstlen,
-                                   DMA_BIDIRECTIONAL);
-
         trace_iwlwifi_dev_tx(trans->dev, skb,
                              &txq->tfds[txq->q.write_ptr],
                              sizeof(struct iwl_tfd),
-                             &dev_cmd->hdr, firstlen,
-                             skb->data + hdr_len, secondlen);
+                             &dev_cmd->hdr, IWL_HCMD_SCRATCHBUF_SIZE + tb1_len,
+                             skb->data + hdr_len, tb2_len);
         trace_iwlwifi_dev_tx_data(trans->dev, skb,
-                                  skb->data + hdr_len, secondlen);
+                                  skb->data + hdr_len, tb2_len);
+
+        if (!ieee80211_has_morefrags(fc)) {
+                txq->need_update = 1;
+        } else {
+                wait_write_ptr = 1;
+                txq->need_update = 0;
+        }
 
         /* start timer if queue currently empty */
         if (txq->need_update && q->read_ptr == q->write_ptr &&